Daily # 4261

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4261

PERIOD COVERED: UT December 15,16,17, 2006 (DOY 3349,350,351)

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8794

NICMOS Post-SAA calibration - CR Persistence Part 5

A new procedure proposed to alleviate the CR-persistence problem of
NICMOS. Dark frames will be obtained immediately upon exiting the SAA
contour 23, and every time a NICMOS exposure is scheduled within 50
minutes of coming out of the SAA. The darks will be obtained in
parallel in all three NICMOS Cameras. The POST-SAA darks will be
non-standard reference files available to users with a USEAFTER
date/time mark. The keyword 'USEAFTER=date/time' will also be added to
the header of each POST-SAA DARK frame. The keyword must be populated
with the time, in addition to the date, because HST crosses the SAA ~8
times per day so each POST-SAA DARK will need to have the appropriate
time specified, for users to identify the ones they need. Both the raw
and processed images will be archived as POST-SAA DARKSs. Generally we
expect that all NICMOS science/calibration observations started within
50 minutes of leaving an SAA will need such maps to remove the CR
persistence from the science images. Each observation will need its
own CRMAP, as different SAA passages leave different imprints on the
NICMOS detectors.

ACS/HRC 11041

ACS CCDs daily monitor

This program consists of a set of basic tests to monitor, the read
noise, the development of hot pixels and test for any source of noise
in ACS CCD detectors. The files, biases and dark will be used to
create reference files for science calibration. This programme will be
for the entire lifetime of ACS. For cycle 15 the program will cover 18
months 12.1.06-05.31.08 and it has been divied into three different
proposal each covering six months. The three proposals are
11041-11042-11043.

FGS 11018

Long Term Stability of FGS1r in Position Mode

It is known from our experience with FGS3, and later with FGS1r, that
an FGS on orbit experiences long term evolution, presumably due to
disorption of water from the instrument's graphite epoxy composits.
This manifests principly as a change in the plate scale and
secondarily as a change in the geometric distortions. These effects
are well modeled by adjustments to the rhoA and kA parameters which
are used to transform the star selector servo angles into FGS {x, y}
detector space coordinates. By observing the relative positions of
selected stars in a standard cluster at a fixed telescope pointing and
orientation, the evolution of rhoA and kA can be monitored and
calibrated to preserve the astrometric performance of FGS1r.

WFPC2 10915

ACS Nearby Galaxy Survey

Existing HST observations of nearby galaxies comprise a sparse and
highly non-uniform archive, making comprehensive comparative studies
among galaxies essentially impossible. We propose to secure HST's
lasting impact on the study of nearby galaxies by undertaking a
systematic, complete, and carefully crafted imaging survey of ALL
galaxies in the Local Universe outside the Local Group. The resulting
images will allow unprecedented measurements of: {1} the star
formation history {SFH} of a 100 Mpc^3 volume of the Universe with a
time resolution of Delta[log{t}]=0.25; {2} correlations between
spatially resolved SFHs and environment; {3} the structure and
properties of thick disks and stellar halos; and {4} the color
distributions, sizes, and specific frequencies of globular and disk
clusters as a function of galaxy mass and environment. To reach these
goals, we will use a combination of wide-field tiling and pointed deep
imaging to obtain uniform data on all 72 galaxies within a
volume-limited sample extending to ~3.5 Mpc, with an extension to the
M81 group. For each galaxy, the wide-field imaging will cover out to
~1.5 times the optical radius and will reach photometric depths of at
least 2 magnitudes below the tip of the red giant branch throughout
the limits of the survey volume. One additional deep pointing per
galaxy will reach SNR~10 for red clump stars, sufficient to recover
the ancient SFH from the color-magnitude diagram. This proposal will
produce photometric information for ~100 million stars {comparable to
the number in the SDSS survey} and uniform multi-color images of half
a square degree of sky. The resulting archive will establish the
fundamental optical database for nearby galaxies, in preparation for
the shift of high-resolution imaging to the near-infrared.

ACS/HRC 10909

Exploring the diversity of cosmic explosions: The supernovae of
gamma-ray bursts

While the connection between gamma-ray bursts {GRBs} and supernovae
{SNe} is now clearly established, there is a large variety of
observational properties among these SNe and the physical parameters
of these explosions are poorly known. As part of a comprehensive
program, we propose to use HST in order to obtain basic information
about the supernovae associated with gamma-ray bursts. HST offers the
means to cleanly separate the light curves of the GRB afterglow from
the supernova, and to remove the contamination from the host galaxy,
opening a clear route to the fundamental parameters of the SN. From
these observations, we will determine the absolute magnitude at
maximum, the shape of the spectral energy distribution, and any change
over time of the energy distribution. We will also measure the rate of
decay of the exponential tail. Merged with the ground-based data that
we will obtain for each event, we will be able to compare our data set
to models and constrain the energy of the explosion, the mass of the
ejecta and the mass of Nickel synthesized during the explosion. These
results will shed light on the apparent variety of supernovae
associated with gamma-ray bursts and X-ray flashes, and on the
relation between these SNe and other, more common varieties of core-
collapse explosions.

NIC1 10889

The Nature of the Halos and Thick Disks of Spiral Galaxies

We propose to resolve the extra-planar stellar populations of the
thick disks and halos of seven nearby, massive, edge-on galaxies using
ACS, NICMOS, and WFPC2 in parallel. These observations will provide
accurate star counts and color-magnitude diagrams 1.5 magnitudes below
the tip of the Red Giant Branch sampled along the two principal axes
and one intermediate axis of each galaxy. We will measure the
metallicity distribution functions and stellar density profiles from
star counts down to very low average surface brightnesses, equivalent
to ~32 V- mag per square arcsec. These observations will provide the
definitive HST study of extra-planar stellar populations of spiral
galaxies. Our targets cover a range in galaxy mass, luminosity, and
morphology and as function of these galaxy properties we will provide:
- The first systematic study of the radial and isophotal shapes of the
diffuse stellar halos of spiral galaxies - The most detailed
comparative study to date of thick disk morphologies and stellar
populations - A comprehensive analysis of halo and thick disk
metallicity distributions as a function of galaxy type and position
within the galaxy. - A sensitive search for tidal streams - The first
opportunity to directly relate globular cluster systems to their field
stellar population We will use these fossil records of the galaxy
assembly process preserved in the old stellar populations to test halo
and thick disk formation models within the hierarchical galaxy
formation scheme. We will test LambdaCDM predictions on sub-galactic
scales, where it is difficult to test using CMB and galaxy redshift
surveys, and where it faces its most serious difficulties.

ACS/WFC 10886

The Sloan Lens ACS Survey: Towards 100 New Strong Lenses

As a continuation of the highly successful Sloan Lens ACS {SLACS}
Survey for new strong gravitational lenses, we propose one orbit of
ACS-WFC F814W imaging for each of 50 high- probability strong
galaxy-galaxy lens candidates. These observations will confirm new
lens systems and permit immediate and accurate photometry, shape
measurement, and mass modeling of the lens galaxies. The lenses
delivered by the SLACS Survey all show extended source structure,
furnishing more constraints on the projected lens potential than
lensed-quasar image positions. In addition, SLACS lenses have lens
galaxies that are much brighter than their lensed sources,
facilitating detailed photometric and dynamical observation of the
former. When confirmed lenses from this proposal are combined with
lenses discovered by SLACS in Cycles 13 and 14, we expect the final
SLACS lens sample to number 80--100: an approximate doubling of the
number of known galaxy-scale strong gravitational lenses and an
order-of-magnitude increase in the number of optical Einstein rings.
By virtue of its homogeneous selection and sheer size, the SLACS
sample will allow an unprecedented exploration of the mass structure
of the early-type galaxy population as a function of all other
observable quantities. This new sample will be a valuable resource to
the astronomical community by enabling qualitatively new strong
lensing science, and as such we will waive all but a short {3-month}
proprietary period on the observations.

ACS/WFC 10882

Emission Line Snapshots of 3CR Radio Galaxies

Radio galaxies are an important class of extragalactic objects: they
are one of the most energetic astrophysical phenomena and they provide
an exceptional probe of the evolving Universe, lying typically in high
density regions but well-represented across a wide redshift range. In
earlier Cycles we carried out extensive HST observations of the 3CR
sources in order to acquire a complete and quantitative inventory of
the structure, contents and evolution of these important objects. We
discovered new optical jets, dust lanes, and revealed point-like
nuclei whose properties support AGN unified schemes. Here, we propose
to obtain ACS emission line images at low and high excitation of 3CR
sources with z0.3, both low- and classical high- power radio
galaxies, as a major enhancement to an already superb dataset. We aim
to probe fundamental relationships between warm optical line-emitting
gas, radio source structure {jets and lobes} and X-ray coronal halos.
We will combine our existing UV images with new emission- line images
to establish quantitative star formation characteristics and their
relation to dust and merging, and with emission-line excitation maps,
test theories on ionization beam patterns and luminosities from active
nuclei. We will seek jet induced star formation and knowing optical
emission-line physics, investigate quantitative jet physics. The
nuclear emission line properties of the galaxies will themselves be
established and used as ingredients in continuing tests of unified AGN
theories. The resulting database will be an incredibly valuable
resource to the astronomical community for years to come.

ACS/WFC 10880

The host galaxies of QSO2s: AGN feeding and evolution at high
luminosities

Now that the presence of supermassive black holes in the nuclei of
galaxies is a well established fact, other questions related to the
AGN phenomena still have to be answered. Problems of particular
interest are how the AGN gets fed, how the black hole evolves and how
the evolution of the black hole is related to the evolution of the
galaxy bulge. Here we propose to address some of these issues using
ACS/WFC + F775W snapshot images of 73 QSO2s with redshifts in the
range 0.3z0.4. These observations will be combined with similar
archival data of QSO1s and ground based data of Seyfert and normal
galaxies. First, we will intestigate whether interactions are the most
important feeding mechanism in high luminosity AGNs. This will be done
in a quantitative way, comparing the asymmetry indices of QSO2 hosts
with those of lower luminosity AGNs and normal galaxies. Second, we
will do a detailed study of the morphology of the host galaxies of
both QSO types, to determine if they are similar, or if there is an
evolutionary trend from QSO2s to QSO1s. The results from this project
will represent an important step in the understanding of AGN
evolution, and may also introduce a substantial modification to the
Unified Model.

ACS/HRC 10878

An ACS Prism Snapshot Survey for z~2 Lyman Limit Systems

We propose to conduct a spectroscopic survey of Lyman limit absorbers
at redshifts 1.7 z 2.2, using ACS/HRC and the PR200L prism. We
have selected 100 quasars at 2.3 z 2.6 from the Sloan Digital Sky
Survey Spectroscopic Quasar sample, for which no BAL signature is
found at the QSO redshift and no strong metal absorption lines are
present at z 2.3 along the lines of sight. The survey has three main
observational goals. First, we will determine the redshift frequency
dN/dz of the LLS over the column density range 16.3 log N_HI 20.3
cm^-2. Second, we will measure the column density frequency
distribution f{N} for the partial Lyman limit systems {PLLS} over the
column density range 16.3 log N_HI 17.5 cm^-2. Third, we will
identify new sightlines for measurements of the primordial D/H ratio.
With this survey, we will also constrain two key quantities of
cosmological relevance: First, the measurements of dN/dz for optically
thick LLS and f{N} for the PLLS are critical to estimating the
attenuation of extragalactic ionizing sources {e.g. QSOs}. Currently,
uncertainties in dN/dz and f{N} are the greatest sources of
uncertainty for inferring the shape and intensity of the UV background
radiation field. Second, we will estimate the amount of metals in the
LLS using the f{N} and ground based observations of metal line
transitions. It is possible that a significant fraction of the
"missing metals" at z~2 are associated with these highly ionized
absorbers. Third, analysis of the LLS lends to investigations of the
interface between galaxies {i.e. the damped Lyman alpha systems} and
the intergalactic medium {i.e. the Lyman alpha forest}. This survey is
ideal for a snapshot observing program, because the on-object
integration times are less than 10 minutes, and the targets cover the
majority of the northern sky.

ACS/HRC/WFPC2/NIC3 10842

A Cepheid Distance to the Coma Cluster

We propose to use the Advanced Camera for Surveys to search for
Cepheid variables in two spiral galaxies in the core of the Coma
cluster. A direct application of the canonical primary distance
indicator at 100 Mpc will measure the far-field Hubble constant free
of many of the systematic uncertainties which beset current
determinations relying on secondary indicators. Establishing the
far-field H_o with Cepheids will provide one of the strongest links in
the extragalactic distance scale and will directly calibrate the
fiducial fundamental plane of elliptical galaxies in Coma. With
ACS/HRC, S/N=5 to 10 or better can be reached for Cepheids with
periods of 40d to 70d at mean light in 5 orbits with the F606W filter
if H_o=72 km/s/Mpc. Efficient detection and phasing can be done with
twelve epochs optimally spaced for periods of 40-70d.

NIC3 10839

The NICMOS Polarimetric Calibration

Recently, it has been shown that NICMOS possesses an instrumental
polarization at a level of 1.2%. This completely inhibits the data
reduction in a number of previous GO programs, and hampers the ability
of the instrument to perform high accuracy polarimetry. In all, 90
orbits of HST data are affected, with potentially many more in Cycle
15. We propose to obtain high signal to noise observations of three
polarimetric standards at the cardinal roll angles of the NICMOS
polarizers for both NIC1 and NIC2. These observations are designed to
fully characterize the instrumental polarization in order for NICMOS
to reach its full potential by enabling high accuracy polarimetry of
sources with polarizations around 1%. The residual polarization will
also be determined as a function of position and spectral energy
distribution. Our group will rapidly turn around the required data
products and produce reports and software for the accurate
representation of the instrumental polarization. These items will be
presented to STScI and for dissemination among the wider astronomical
community.

NIC2, ACS/WFC 10802

SHOES-Supernovae, HO, for the Equation of State of Dark energy

The present uncertainty in the value of the Hubble constant {resulting
in an uncertainty in Omega_M} and the paucity of Type Ia supernovae at
redshifts exceeding 1 are now the leading obstacles to determining the
nature of dark energy. We propose a single, integrated set of
observations for Cycle 15 that will provide a 40% improvement in
constraints on dark energy. This program will observe known Cepheids
in six reliable hosts of Type Ia supernovae with NICMOS, reducing the
uncertainty in H_0 by a factor of two because of the smaller
dispersion along the instability strip, the diminished extinction, and
the weaker metallicity dependence in the infrared. In parallel with
ACS, at the same time the NICMOS observations are underway, we will
discover and follow a sample of Type Ia supernovae at z 1. Together,
these measurements, along with prior constraints from WMAP, will
provide a great improvement in HST's ability to distinguish between a
static, cosmological constant and dynamical dark energy. The Hubble
Space Telescope is the only instrument in the world that can make
these IR measurements of Cepheids beyond the Local Group, and it is
the only telescope in the world that can be used to find and follow
supernovae at z 1. Our program exploits both of these unique
capabilities of HST to learn more about one of the greatest mysteries
in science.

ACS/HRC 10800

Kuiper Belt Binaries: Probes of Early Solar System Evolution

Binaries in the Kuiper Belt are a scientific windfall: in them we have
relatively fragile test particles which can be used as tracers of the
early dynamical evolution of the outer Solar System. We propose to
continue a Snapshot program using the ACS/HRC that has a demonstrated
discovery potential an order of magnitude higher than the HST
observations that have already discovered the majority of known
transneptunian binaries. With this continuation we seek to reach the
original goals of this project: to accumulate a sufficiently large
sample in each of the distinct populations collected in the Kuiper
Belt to be able to measure, with statistical significance, how the
fraction of binaries varies as a function of their particular
dynamical paths into the Kuiper Belt. Today's Kuiper Belt bears the
imprints of the final stages of giant-planet building and migration;
binaries may offer some of the best preserved evidence of that
long-ago era.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTARS:

10559 - GSACQ(1,2,1) failed, Search Radius Limit Exceeded on FGS 1

Upon acquisition of signal at 350:06:57:46 vehicle was in gyro control
with FGS 1 search radius limit flag set. GSACQ(1,2,1) at 350:06:37:37
failed with search radius limit exceeded. OBAD data prior to GSACQ is
unavailable until engineering dump is taken. OBAD map after GSACQ
failure showed RSS error of 2.78 arcseconds.

ReACQ(1,2,1) scheduled at 350:09:47:59 failed to RGA hold with search
radius limit exceeded. OBAD data prior to ReACQ showed RSS attitude
correction of 7.22 arcseconds.

During ReAcq at 09:47:59z we monitored PMT count for FGS 1. The
highest value notes was 18.

Subsequent REacqs(1,2,1) scheduled at 350/11:23:52, 350/12:59:46,
350/14:35:41 using the same star id failed to RGA Hold (Gyro Control)
due to search radius limit exceeded on FGS-1. Additional 486(x3)ESB
"a05" (FGS Coarse Track failed - Search Radius Limit Exceeded) were
received.

ReACQ(1,2,1) scheduled at 350:08:12:04 failed to RGA hold with search
radius limit exceeded. OBAD data prior to ReACQ showed RSS attitude
correction of 5.04 arcseconds. OBAD map after GSACQ failure showed RSS
error of 4.42 arcseconds.

10560 - GSACQ(2,3,3) failed, Search Radius Limit Exceeded on FGS 3

Upon Acquisition at 352/08:40:31, GSACQ(2,3,3) scheduled at
352/07:55:17 failed due to Search Radius Limit Exceeded on FGS 3. One
486 status buffer A05 message (FGS Coarse Track failed- search Radius
Limit exceeded) was received. OBAD data prior to GSACQ is unavailable
until engineering dump. OBAD map after GSACQ failure showed RSS error
of 36.03 arcseconds.

10561 - GSACQ(1,3,1) failed, Search Radius Limit Exceeded on FGS 1

GSACQ(1,3,1) scheduled at 352:09:31:06 failed at 09:36:49 due to
search radius limit exceeded. OBAD data prior to GSACQ is RSS of
13.08. OBAD map after GSACQ is unavailable until engineering dump is
taken. RSS was 12.73 arcseconds

COMPLETED OPS REQUEST:
17976-0 - Genslew for proposal 10847 - slot 4
17977-0 - Genslew for proposal 10847 - slot 5
17978-0 - Genslew for proposal 10847 - slot 6
17979-0 - Genslew for proposal 10896 - slot 7
17980-0 - Genslew for proposal 10896 - slot 8
17981-0 - Genslew for proposal 10896 - slot 9


COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSacq 22 19
FGS REacq 23 18
OBAD with Maneuver 90 90

SIGNIFICANT EVENTS: (None)